1. Field of the Invention
The invention relates to a fuel feed module for feeding fuel to an internal combustion engine, especially for use in a motor vehicle.
2. Prior Art
In motor vehicles, for feeding the fuel from a fuel tank to the engine, fuel pumps that are installed in the interior of the fuel tank are used. These fuel pumps are typically disposed on the bottom of the tank and are surrounded by a so-called reservoir cup, by which the fuel level directly around the fuel pump is kept at a predetermined level. This assures that while driving around a curve or on a hill, even if the fuel tank is already been pumped partly empty, the engine will reliably be supplied with fuel. The reservoir cup jointly with the fuel pump forms the fuel feed module. In order on the one hand to fill the reservoir cup with fuel from the tank, a suction jet pump is often used, which is driven by the fuel fed back by the engine. The fed-back fuel can, however, also flow directly into the reservoir cup. Furthermore, reservoir cups typically have two fuel filters, the first of which is located on the intake side upstream of the fuel pump, while the second, finer filter is downstream of the fuel pump.
A fuel module as defined by the preamble to claim 1 is disclosed for instance by German Patent Disclosure DE 196 19 992. In this construction, the installation height of the fuel pump inside the reservoir cup is determined on the one hand by the dimensions of the fuel pump but on the other by the upstream coarse filter and an intake nozzle with which the fuel is aspirated through the coarse filter. The intake nozzle is disposed together with the coarse filter above the bottom of the reservoir cup, so that the fuel flows in substantially at a right angle from below.
In this arrangement, however, the following problems arise. If the fuel level in the reservoir cup is below the coarse filter, the fuel feed pump and thus the engine are no longer supplied with fuel. Analogously to this poor residual aspiration performance, problems arise when the tank and the reservoir cup are first filled, because in this case as well, there must first be a minimum level of fuel in the reservoir cup before the fuel feed pump can begin its operation.